The one year subscription will also get you two free books (as PDF downloads)
(note: these are new books, and not for sale separately):

"201 Tricky Calcudoku Puzzles, Extra".
The 41 difficult puzzles in this book are worth 5 points each.(this book is not for sale separately)

"102 Large Calcudoku Puzzles, Extra".
The 32 difficult puzzles in this book are worth 10 points each.(this book is not for sale separately)

New: when you renew your annual subscription, you'll get the book "51 Advanced Puzzles"
(also as a PDF download, and also not for sale separately). When you renew a 2nd time, you'll get volume II of this book:

The six month subscription will get you one free book (of the first two,
specify which one you prefer when ordering).

Subscriptions are not automatically renewed (you can add a new subscription at any time).

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Note: after payment, wait until you return to the site, then your subscription will be started automatically.

It is also possible to become a subscriber by bank transfer to IBAN NL96INGB0006238302 (BIC/SWIFT code: INGBNL2A) to "Patrick Min Computer Programming", the Netherlands. Don't forget to put your username (!) in the transfer comments, and (for the 6 month subscription) the book you'd like.

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